PRELIMINARY CONSIDERATIONSIN OPERATIVE DENTISTRYSUBMITTED BY :EKTA CHAUDHARYBDS INTERN
PATIENT AND OPERATOR POSITIONS• Efficient patient and operator positions are beneficial for the welfare of both individuals.• A patient who is in a comfortable position is more relaxed,has less muscular tension and is more capable of cooperating with the dentist.• By using proper operating positions and good posture the operator experiences less physical strain and fatigue and reduces the possibility of developing musculoskeletal disorders.
CHAIR AND PATIENT POSITIONS• Modern dental chairs are designed to provide total body support in any chair position.• Chair design and adjustment permit maximal operator access to the work area.• The adjustment control switches should be conveniently located.• Some chairs are also equipped with programmable operating positions.• To improve infection control,chairs with a foot switch for patient positioning are recommended.
• The patient should have direct access to the chair.• The chair height should be low,backrest upright,armrest adjusted to allow the patient to get into the chair.• The headrest cushion is adjusted to support the head and elevate the chin slightly away from the chest.• In this position neck muscle strain is minimal and swallowing is facilitated.
COMMON PATIENT POSITIONS• SUPINE POSITION.• RECLINED 45 DEGREES .
SUPINE POSITION• In this position the patient’s head,knees and feet are approximately at the same level.• The patient’s head should not be lower than the feet ; the head should be positioned lower than the feet only in case of emergency (syncope)• When the operation is completed the chair should be placed in an upright position so that the patient can leave the chair easily preventing undue strain and loss of balance.
FOR RIGHT HANDEDOPERATING POSITIONS OPERATOR 1)RIGHT FRONT POSITION(7-O’CLOCK) 2)RIGHT POSITION (9-O’CLOCK) 3)RIGHT REAR POSITION(11-O’CLOCK) 4)DIRECT REAR POSITION(12-O’CLOCK) FOR LEFT HANDED OPERATORS 1)LEFT FRONT (5- O’CLOCK) 2)LEFT (3-O’CLOCK) 3)LEFT REAR (1-O’CLOCK)
RIGHT FRONT POSITION• Facilitates examination and work on Mandibular anterior teeth, Mandibular posterior teeth (especially on the right side) , Maxillary anterior teeth.• It is often advantageous to have the patient’s head rotated slightly towards the operator.• 7-o’ clock position
RIGHT POSITION• The operator is directly to the right of the patient.• This position is convenient for operating on the Facial surfaces of the maxillary and mandibular right posterior teeth and occlusal surfaces of the mandibular right posterior teeth.• 9-o’clock position
RIGHT REAR POSITION(11-o’clock)• Position of choice for most operations.• Most areas of mouth are accessible and can be viewed directly or indirectly using a mouth mirror.• The operator is behind and slightly to the right of the patient.• The left arm is positioned around the patient’s head.• The lingual and incisal surfaces of maxillary teeth are viewed in the mouth mirror.• Direct vision may be used on the mandibular teeth , particularly on the left side.
DIRECT REAR POSITION• This position has limited application.• Used primarily for operating on the lingual surfaces of mandibular anterior teeth.• The operator sits behind the patient and looks down over the patient’s head.• 12-o’clock position.
GENERAL CONSIDERATIONS• When operating in the maxillary arch , the maxillary occlusal surfaces should be oriented approximately perpendicular to the floor.• When operating in the mandibular arch, the mandibular occlusal surfaces should be oriented approximately 45 degrees to the floor.• The face of the operator should not come in close proximity to the patient.The ideal distance similar to that for reading a book should be maintained.
• A proper operator does not rest forearms on the patient’s shoulders or hands on the patient’s face.• The patient’s chest should not be used as an instrument tray.• When operating for an extended period a certain amount of rest and muscle relaxation can be obtained for the operator by changing operating positions.
OPERATING STOOLS• The stools should be on casters for mobility.• It should be sturdy and well balanced to prevent tipping or gliding away from the dental chair.• The seat should be well padded with smooth cushion edges and should be adjustable up and down.• The backrest should be adjustable forward and backward and up and down.• The operator should not be balanced on the stool using it as a third leg of a tripod.• The operator should sit back on the cushion, using the entire seat, not just the front edge.
• The upper body should be positioned so that the spinal column is straight or bent slightly forward and supported by the backrest of the stool.• The thighs should be parallel to the floor and the lower legs should be perpendicular to the floor.• Feet should be flat on the floor.• The seated work position for the assistant is essentially the same as for the operator except that the stool is 4-6 inches higher for maximal visual access.
INSTRUMENT EXCHANGE• All instrument exchanges between the operator and assistant should occur in the exchange zone below the patient’s chin and several inches above the patient’s chest.• Instruments should not be exchanged over the patient’s face.• Any sharp instrument should be exchanged very carefully.• The exchange should not be forceful.• Each person should be sure that the other has a firm grasp on the instrument before it is released.
MAGNIFICATION• Magnification achieved with either surgical loupes or dental microscopes enlarges the operating site.• Both these factors allow the clinician to visualise features not otherwise perceptible to the naked eye. It is for these reasons that it is universally recognised that the use of magnification in dentistry not only improves the quality of care provided to patients, but also expands the range of treatments that can be offered.
The Benefits Of Magnification• Magnified Image• Brilliant Illumination• Better Posture and Improved Comfort• Increasing Precision• Improved Dental Care• Additional Treatment Options• Improved Profitability
IsolationIsolation is very important for• controlling moisture• Retraction and• Patient protection• To improve the efficacy of operator
Goals of Isolation• Moisture control• Retraction and access• Safe and aseptic operating field• Prevent accidental swallowing of restorative materials and instruments• Prevents Bacterial contamination from saliva
Methods of Fluid Control Mechanical Chemical 1.Rubber Dam 1.Drugs 2.High Volume vaccum 2.Local Anaesthesia 3.Saliva Ejector 4.Svedopter 5. Cotton Rolls 6.Absorbent Pads 7.Gingival Retraction cord 8.Gauze Pieces
Rubber Dam• The Rubber Dam is a flat, thin sheet of latex or non latex that is held by a clamp(retainer) and a frame that is perforated to allow the teeth that will be worked on to protrude through the perforations in the sheet while all the other teeth are covered and protected by the rubber dam.
Advantages1. Isolation of the operating field2. Improved accessibility and visibility3. Improved properties of dental materials4. Protection of patient’s airway5. Protection of patient’s soft tissues6. High patient acceptance – Allow to Relax7. No gag reflex8. Time saving9. Operating efficiency
Disadvantages• Time consumption• Patient’s objectionConditions where rubber dam is not used:• partially erupted teeth• Some third molars• Extremely malpositioned teeth• Asthmatic patients• Psychological reasons• Latex allergy
MATERIALS AND INSTRUMENTS1. Rubber dam Sheets2. Rubber dam holder3. Rubber dam retainer(clamp)4. Plastic tray for holding the clamp5. Retainer forceps6. Punch7. Napkin8. Lubricant
1) RUBBER DAM SHEET •Available in 5x5 inches or 6x6inches •Thin --------------- 0.15mm •Medium------------0.2mm •Heavy--------------0.25mm •Special heavy----0.35mm •Colours available --- green , blue •Two surfaces----Shiny surface and dull surface. •Dull surface placed facing the occlusal side of the isolated teeth.
2)RUBBER DAM FRAME• Maintains the borders of rubber dam in position.• Young’s rubber dam frame is a U-shaped metal frame with small metal projections for securing the borders of the rubber dam.• An optional adjustable neck strap may be placed behind the patient’s neck and is attached to two hooks , one in the middle of each side of the frame.
3)RETAINERS• Consists of four prongs and two jaws connected by a bow.• Used to anchor the dam to the most posterior tooth to be isolated.• Also used to retract the gingival tissues.• When positioned on tooth, a properly selected retainer should contact the tooth in four areas- two on the facial surface and two on the lingual surface.(this four point contact prevents rocking or tilting of the retainer).
• Winged and wingless retainers are available.• The wings are designed to provide extra retraction of the rubber dam from the operating field and to allow attachment of the dam to the retainer.• Disadvantage of the winged retainer is that the wings often interfere with the placement of matrix bands, wedges.
4)RETAINER FORCEPS Used for placement and removal of the retainer from the tooth.
5)RUBBER DAM PUNCH• For producing holes in the rubber dam for the teeth• It is an instrument having a rotating metal table with six holes of varying sizes and a tapered sharp pointed puncher• Larger holes-Molars• Medium sized holes-premolars , canines and upper incisors• Smallest hole –lower incisors
6)NAPKIN• Placed Between rubber dam and patients skin• Reduce allergic reaction• Absorbs saliva• Acts as a cushion.
7)LUBRICANT• A water soluble lubricant applied in the area of the punched holes facilitates the passing of the dam septa through the proximal contacts.• Rubber dam lubricant is commercially available.• Other options – shaving cream , soap slurry
PLACEMENT OF THE RUBBER DAM2 methods1. Dam first technique2. Clamp first technique
Removal of rubber dam• Cutting the septa• Removing the retainer• Removing the dam• Wiping the lips• Rinsing the mouth• Massaging the tissue and• Examining the dam
Cotton roll isolation and cellulosewafers• They are absorbents• Provide moisture control with saliva ejector• Isolation of maxillary teeth - cotton roll in facial vestibule• Isolation of mandibular teeth - medium sized cotton in vestibule and large one between teeth and tongue• Cellulose wafers - retraction and additional absorbency
Gauze pieces•Supplied inpieces of 2”x2”or larger•Act as throatscreens•Better toleratedby delicatetissues
Absorbent pads/wafers•Made up ofcellulose•More absorbentthan cotton rolls orgauzes•Commonly usedinside the cheeks tocover the parotidduct
High volume evacuators•Excellent lipretractionAdvantages•Toxic material isreadily removed•Decreases treatmenttime•Removes debris
SALIVA EJECTORS• For suctioning water and debris• Used as an adjunct to high volume evacuators• Placed in the corner of the mouth opposite the quadrant being treated• Advantages -improve accessibility and visibility -maintains a clean,dry operating field.
Technique for placement of cord1.Retracting the cordfrom the bottle2.Cord twisted
3.Loop of cord formedaround the tooth andheld tightly 4.Cord should be insertedstarting from the mesialsurface of the tooth untilthe distal surface
5.Cord should be tuckedinto the sulcusprogressively6.Holding of cord
7.Angling of instrument towardthe root 8.excess cord cut off near interproximal area of mesial surface
9.After cutting off the excess at the mesial end thedisal end of cord is tucked until it overlaps thetucked mesial end.
MOUTH PROPS• With the use of mouth props, the patient is relieved of the responsibility of maintaining mouth opening,permitting added relaxation.• Mouth props of different designs and different materials are available.• They are available as either a block type or a ratchet type.
DRUGS• Use of drugs to control salivation is rarely indicated in restorative dentistry and is limited to atropine.• Atropine is contraindicated for nursing mothers and patients with glaucoma.
SUMMARY• A thorough knowledge of the preliminary procedures as discussed reduces the physical strain on the dental team associated with daily dental treatment , reduces patient anxiety associated with dental procedures, enhances moisture control and thus improving the quality of operative dentistry.
REFERENCES :• Sturdevant’s Art and Science of Operative Dentistry.